Break-in fuel



Patented Dec. 9, 1947 UNITED STATE 2,432,109 BREAK-m FUEL William A. Zisman. R. Baker, Mount Murphy, Jr.,

No Drawing.

Washington, D. Ranier, Md, and Washington, D. 0.

Application September 30, 1944,

0., Hayward Charles M.

Serial No. 556,652 4 Claims. (01. 44-76) (Granted under the act amended April 30,

Our invention relates to a new composition of matter and specifically it relates to new breakin type fuels for internal combustion engines.

It is standard practice among engine manufacturers to operate the engines produced for a given number of hours as a test and to break them in or wear some of the very stiff newness out of joints. This practice is generally quite costly in that it ties up engines for long periods and consumes much time, particularly if the test run is extended to make it a break-in run. The desirability of accelerating the break-in time of an engine has long been appreciated, but little has been done to accomplish it. The only feasible method of accelerating break-in time appeared to be by addition of some abrasive to the lubricating system. This method, although workable, is attended tages, namely, the difficulty of obtaining a fine enough abrasive, keeping it in suspension and controlling the wear of parts.

It is the principal object of our invention to provide a novel fuel composition for use in accelerated break-in runs of internal combustion engines.

It is a secondary object of our invention to provide a fuel composition suitable not only for accelerated break-in runs of internal combustion engines, but also for polishing and burnishing engine cylinders and pistons and for removing small amounts of hard carbon from the engine.

Our invention comprises a fuel for internal combustion engines possessing the features, properties, and the relation of components,

by numerous dlsadvanwhich will be exemplified in the product hereinafter described and the scope of the invention will be indicated in the claims.

In our copending application, Serial Number 556,651 filed on even date herewith, we have described a method of performing accelerated break-in runs and of applying a superior final finish to the cylinder walls and pistons.

We have devised a method and composition whereby a very finely divided abrasive of characteristic spherical or globular particle shape can be generated in the cylinders of a running engine and scattered over the inner surfaces of the cylinders to be worked between th juxtaposed cylinder walls and pistons to polish and break-in the engine. In particular we have found that by operating the engine on a fuel which is essentially a solution of an organosilicon compound, the compound will burn in the cylinders to form a very finely divided silicon of March 3, 1883, as

dioxide, which oxide will act as a polishing agent in the engine. Apparently, in operation, the fuel and, consequently, the organo-siiicon compound dissolved therein are sprayed into the engine cylinder in very finely divided form or actually vaporized just before entry into the The organocompoundis injected into the cylinder in very finely divided form and is decomposed to silica with explosive violence when the fuel in the cylinder ignites.

The reaction conditions in the cylinder are such that they favor the formation of finely divided particles whose shape is spherical or globular and whose size we have found is less than one micron. Often the particle size is less than 0.05 micron or 500-angstrom units. The fine particles thus scattered throughout the interior of the cylinder are worked or rolled between the piston and the cylinder walls and by their rolling action flatten out many of the microscopic or submicroscopic irregularities left in the juxtaposed cylinder and piston surfaces by the lapping or finishing step used in the manufacture of the engine. Furthermore the particles are so light and fine that they blow out through the engine exhaust line with the fuel smoke without permitting the accumulation of any substantial quantity in the cylinder.

In the practice of our invention, organo-sllicon compounds of the following general types can be used: R\ /R a R R R r i /Si\ -si-o-si-o-si- -Si-O-8i-0-Si o 0 t t t I l R R B B (l) where R is an alkyl, aryl, alkaryl or aralkyl radical. It will be noted that the above classes of compounds include silicon compounds having ester-like structures (1) silicon compounds having ether-like structures (2), and silicon compounds containing both ether-like and esterlike linkages (3). Typical of the compounds are ethyl orthosilicate, propyl orthosilicate, amyl orthosilicate and various alkyl, aryl, aralkyl and alkaryl polysiloxanes such as those now being manufactured and offered to the trade as silicone fluids and plastics. I

In series of tests made on new engines we used substantially saturated solutions of the organo-silicon compounds in the hydrocarbon fuel for the engine. In most cases this was satisfactory for the compounds of the types 1. A break-in fuel for internal combustion en-v mentioned above are of very limited solubility gines adapted tofrecluce the break-in time from in hydrocarbons and the possibility of getting too that normally required consisting of a hydrocarengine is rather remote. 2. A break-in fuel for internal combustion en- The method of making up the fuel containing gines adapted to reduce the break-in time from the organo-silicon additive is quite simple. Since that normally required consisting of a. hydro- & solution of about 0.5% to 1% concentration is carbon fuel for the engines substantially satgenerally best, one part by weight of the silicon in urated with about 0.5% by weight of monomeric compound selected, e. g., ethyl silicate, is added to tetra ethyl orthosilicate. about one hundred parts of fuel and the mixture 3. A break-in fuel for internal combustion enagitated until the silicate is dissolved. Altergines adapted to reduce the break-in time from natively, when the silicious compound is only that normally required consisting of a hydroslightly soluble in the hydrocarbon fuel'e. g., as 15 carbon fuel for the engines substantially satis true with most polysiloxanes, it is often easier urated with about 0.5% by weight of monomeric to add an excess to the fuel to be used, agitate tetra propyl orthosilicate. the mixture for a few hours and separate the 4. A break-in fuel for internal combustion enundissolved liquid by decantation. Although it is gines adapted to reduce the break-in time from desirable that the fuel used have the silicon com- 20 that normally required consisting of a hydrosmall amount of undissolved silicon compound urated with about 0.5% by weight of monomeric remains in the hydrocarbon fuel. Since certain tetra amyl orthosilicate.

changes may be made in carrying out the above WILLIAM A. ZISMAN. process without departing from the scope of the 5 HAYWARD R. BAKER. invention, it is intended that all matter contained CHARLES M. MURPHY, Jn. in the above description shall be interpreted as illustrative and not in a limiting sense. REFERENCES CITED The invention described harem may be manu The following references are of record in the factured and used by or for the Government of 30 me of this patent:

purposes without the payment of any royalties UNITED STATES PATENTS thereon or therefor. Number Name Date Having described our invention, what we claim 2,212,992 Sowa Aug. 27, 1940 as new and desire to secure by Letters Patent is: 35 2,375,007 Larsen May 1, 1945 

